body {
  margin: 0;
  padding: 0;
  font-family: 'Arial', sans-serif;
  background: linear-gradient(to right, #0f2027, #203a43, #2c5364);
  background-size: cover;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

.container {
  box-shadow: 0 0 5px #03e9f4, 0 0 25px #03e9f4,
    0 0 50px #03e9f4, 0 0 100px #03e9f4;
  border: 2px solid #03e9f4;
  overflow: hidden;
  margin-bottom: 0;
  position: relative;
  width: 50vw;
  height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
}

.container>span {
  position: absolute;
}

.container>span:first-child {
  right: 0;
  top: -10%;
  height: 200%;
  width: 5px;
  background: linear-gradient(to top, transparent, rgb(3, 244, 192) 30%, #03e9f4 60%, rgb(0, 77, 243) 100%);
  animation: move6 1s linear infinite;
  animation-direction: reverse;
  animation-timing-function: ease-in-out;
}

.container>span:first-child+span {
  left: 0;
  width: 5px;
  bottom: -10%;
  height: 200%;
  background: linear-gradient(to bottom, transparent, rgb(3, 244, 192) 30%, #03e9f4 60%, rgb(0, 77, 240) 100%);
  animation: move7 1s linear 3s infinite;
  animation-direction: reverse;
  animation-timing-function: ease-in-out;
}





@keyframes move6 {
  0% {
    top: -100%
  }

  50% {
    top: 0%
  }

  100% {
    top: -100%
  }
}

@keyframes move7 {
  0% {
    bottom: -100%
  }

  50% {
    bottom: 0%
  }

  100% {
    bottom: -100%
  }
}